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<head>
  <meta charset="UTF-8">
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  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <script>
//    let arr  = [ 'c','a','b','v']
// let o = {}
// for(var k of arr) {
// o[k] = k
// }

// console.log(o);
 new Promise((res,err)=> {
   let success = true
   let a = '我就试试'
   if(success) {
     res('我是正确的回调'+a)
   } else {
     err('我是错误的')
   }
 }).then(res=>{
   console.log(res);
 })

  </script>
</body>

</html>
